A low-cost adaptive data separation method for the flash translation layer of solid state drives

Abstract

Solid state drives (SSDs) have shown great potential for data-intensive computing due to their much higher throughput and lower energy consumption compared to traditional hard disk drives. Within an SSD, its Flash Translation Layer (FTL) is responsible for exposing the SSD's flash memory storage to the computer system as a simple block device. The FTL design is one of the dominant factors determining an SSD's lifespan and the amount of performance degradation. To deliver better performance, we propose a new, low-cost, adaptive separation-aware flash translation layer (ASA-FTL) that combines data clustering and selective caching of recency information to accurately identify and separate hot/cold data while incurring minimal overhead. Using simulations of ASA-FTL with real-world workloads, we have shown that our proposed approach reduces the garbage collection overhead by up to 28% and the overall response time by 15% compared to one of the most advanced existing FTLs.